vue+elementUI+transition实现鼠标滑过div展开内容，鼠标划出收起内容，加防抖功能

一、场景

这两天做项目，此产品提出需求 要求详情页的顶部区域要在鼠标划入后展开里面的内容，鼠标划出要收起部分内容，详情底部的内容高度要自适应，我这里运用了鼠标事件+transition实现，加上lodash debounce进行防抖，下面是具体实现代码

二、实现代码

1.子组件代码结构

代码如下（示例）：

<template>
  <div
    class="project-header"
    @mouseenter="enterFun()"
    @mouseleave="leaveFun()"
    ref="project-header"
  >
    <div class="project-header-top">
    顶部要显示的部分
    </div>
    <div class="bottom" v-show="showProjectHeaderBottom">
    顶部要隐藏的部分，鼠标划入显示
    </div>
  </div>
</template>

<script>
import { debounce } from 'lodash';//npm install lodash引入
export default {
  name: '',
  components: {},
  props: {
  },
  data() {
    return {
      showProjectHeaderBottom: false,//控制顶部要隐藏的显隐
    };
  },
  methods: {
    // 鼠标滑过
    enterFun:debounce(function(){
      this.showProjectHeaderBottom = true;
      this.$emit('getHeight', 'hover');
    },100),
    // 鼠标划出
    leaveFun:debounce(function(){
      this.showProjectHeaderBottom = false;
      this.$emit('getHeight', null);
    },100),
  },
};
</script>
<style lang="scss" scoped>
.project-header {
  height: 68px;
}
</style>

2.父组件

代码如下（示例）：

<template>
  <div class="project-detail" ref="project-browse" >
    <Header
      ref="project-detail-top"
      class="project-detail-top"
      @getHeight="getHeight"
    >
    </Header>
    <div class="tab-content" style="position: relative" ref="tab-content">
    </div>
  </div>
</template>

<script>
import Header from './components/detailHeader.vue';
export default {
  name: '',
  components: {  Header},
  props: {},
  data() {
  },
  methods: {
    mountedInit() {
     this.getHeaderheight();
      window.addEventListener('resize', this.getHeaderheight);
    },
    getHeaderheight(type) {
      this.$nextTick(() => {
        let projectHeader = type === 'hover' ? 208 : 60;
        document.querySelector('.tab-content .el-tabs__content').style.overflow = type === 'hover' ? 'hidden' : 'auto';
        let height = this.$refs['project-browse']?.offsetHeight - projectHeader;
        this.$refs['tab-content'].style.height = height + 'px';//自适应
        this.$refs["project-detail-top"].$el.style.height=projectHeader+ 'px';
      });
    },

  },
  created() {
    this.createdInit();
  },
  mounted() {
    this.mountedInit();
  },
};
</script>
<style lang="scss" scoped>
.project-detail-top {
  transition: height 0.2s ease-in-out;
  overflow: hidden;
}
</style>